This project has two major components- preclinical and clinical. I am currently collaborating with members of NINDS in obtaining new agents and testing them in a nonhuman primate model prior to evaluating these agents in pediatric patients. The ideal agent for testing is a nonneurotoxic agent with poor blood:brain barrier penetration that has demonstrated activity in vitro against CNS tumor cell lines. In the past year, we have evaluated a potential agent and have plans to evaluate a number of additional agents. IL-13 PE has undergone extensive preclinical testing in the Surgical Neurology Branch. It has been used in national consortia studies for administration to adult patients with supratentorial gliomas. Recently, data has become available from autopsy specimens from children with diffuse pontine gliomas, demonstrating extensive expression of IL13 within these tumors. We currently have an IRB-approved protocol but are awaiting FDA approval to begin patient accrual.